form validation in asp.net mvc ( using javascript )

Question

i'm new to asp.net mvc and i have aform with some validation and i want to validate it in client side so i write normal script in javascript to be more specefic my problem was the return false ( as it shouldn't send any data to server and still in apage but this doesn't happen) ,note : i test the script in normal html file with js and works fine but as i said i'm not familiar with mvc so i want to know if there any thing i have missed to work in it and if there any reference to any toturial in this specefic point it would be good , as i noticed in this place ( there's no place for beginners :); this is a snippet of my code too

@model registerationex.Models.register

@{
    ViewBag.Title = "Create";
}


<h2>Create</h2>

@using (Html.BeginForm()) {
    @Html.ValidationSummary(false)

    <fieldset>
        <legend>register</legend>

        <div class="editor-label">
            @Html.LabelFor(model => model.name)
        </div>

        <div class="editor-field">
            @Html.EditorFor(model => model.name)
            <span id="error"></span>
            @Html.ValidationMessageFor(model => model.name)
        </div>

        <div class="editor-label">
            @Html.LabelFor(model => model.email)
        </div>

        <div class="editor-field">
<input class="text-box single-line" data-val="true" data-val-required="The email field is required." id="email" name="email" type="text" value="" onblur="checkuser(email);">      
                  <span id="erroruser"></span>
            @Html.ValidationMessageFor(model => model.email)
        </div>

        <div class="editor-label">
            @Html.LabelFor(model => model.age)
        </div>
        <div class="editor-field">
            @Html.EditorFor(model => model.age)
            <span id="errorage"></span>
            @Html.ValidationMessageFor(model => model.age)
        </div>

        <p>
            <input type="submit" value="Create" onclick="allvalidate();"  />
        </p>
    </fieldset>
}

<div>
    @Html.ActionLink("Back to List", "Index")
</div>



@section Scripts {
    @Scripts.Render("~/bundles/jqueryval")

}

<script>
    function allvalidate() {
        var validated = true;
        if (!validate()) validated = false;
        if (!checkAge(age)) validated = false;
        if (!checkuser(email)) validated = false;

        return validated;
    }


    function validate() {
        var txtf = document.getElementById('name');
        if (txtf.value == 0 || txtf.value == null) {
            document.getElementById('error').innerText = ('you must enter firstname');
            document.getElementById('error').style.color = 'red';

            txtf.focus();
            return false;
        }
        else {
            document.getElementById('error').innerText = ('');
            return true;
        }
    }


    function checkAge(input) {
        if (input.value < 18 || input.value > 70) {
            document.getElementById('errorage').innerText = ('age must be from 18 :70');
            document.getElementById('errorage').style.color = 'red';
            return false;
        }
        else {
            document.getElementById('errorage').innerText = ('');
            return true;
        }

    }


    function checkuser(input) {
        var pattern = '^[a-zA-Z]+$';
        if (input.value.match(pattern)) {
            document.getElementById('erroruser').innerText = '';
            return true;
        }
        else {
            document.getElementById('erroruser').innerText = ('enter valid email');
            document.getElementById('erroruser').style.color = 'red';

            return false;
        }


    }



</script>

Answer 1

You have included @Scripts.Render("~/bundles/jqueryval") which by default jquery.validate.unobtrusive.js , so delete all your scripts and make use of the features which come with MVC. Simply add the validation attributes to your properties.

[Required(ErrorMessage = "you must enter firstname")]
public string name { get; set; }

[EmailAddress(ErrorMessage = "enter valid email")]
public string email { get; set; }

[Required(ErrorMessage = "you must your age")]
[Range(18, 70, ErrorMessage = "age must be from 18 : 70")]
public int age { get; set; }

Now everything that your scripts are trying to do (badly) is done out of the box (assuming you have not disabled unobtrusive validation) and the form will not submit until the errors are corrected. You also now get server side validation which is the essential validation (client side validation is just a nice bonus, but anyone can easily by pass it) so you must always validate on the server

Also replace you manual attempt to create an input for the email property with @Html.EditorFor(m => m.email) and remove all the onclick attibutes

Side note: you regex ^[a-zA-Z]+$ wont even allow a valid email address to be entered (it does not even allow the @ or . characters!). Using the EmailAddress] attribute will generate the correct regex which is (from jQuery Validation 1.9.0 )

^((([a-z]|\d|[!#\$%&'\*\+\-\/=\?\^_`{\|}~]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])+(\.([a-z]|\d|[!#\$%&'\*\+\-\/=\?\^_`{\|}~]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])+)*)|((\x22)((((\x20|\x09)*(\x0d\x0a))?(\x20|\x09)+)?(([\x01-\x08\x0b\x0c\x0e-\x1f\x7f]|\x21|[\x23-\x5b]|[\x5d-\x7e]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])|(\\([\x01-\x09\x0b\x0c\x0d-\x7f]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF]))))*(((\x20|\x09)*(\x0d\x0a))?(\x20|\x09)+)?(\x22)))@((([a-z]|\d|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])|(([a-z]|\d|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])([a-z]|\d|-|\.|_|~|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])*([a-z]|\d|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])))\.)+(([a-z]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])|(([a-z]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])([a-z]|\d|-|\.|_|~|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])*([a-z]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])))$

Answer 2

The allvalidate() function should look like this ( call submit function, not return value) :

<script>
        function allvalidate() {
            var validated = true;
            if (!validate()) validated = false;
            if (!checkAge(age)) validated = false;
            if (!checkuser(email)) validated = false;

            if(validated)
                $('[type="submit"]').submit();
        }
   </script>